Liner for prosthetic and orthopedic systems

ABSTRACT

A liner is arranged for use in prosthetic and orthopedic devices. The liner defines first and second end portions, and inner and outer surfaces. The liner includes an inner layer having a frictional component and forms at least part of the periphery of the inner liner surface. The inner layer defines a plurality of apertures. A porous element is in communication with the inner liner surface and is connected to the inner layer such that the apertures permit a transfer of air from the inner surface to the porous element. A base layer adjoins the porous element and extends between the first and second end portions of the liner.

FIELD OF THE INVENTION

The present invention relates generally to a liner for prosthetic andorthopedic devices. More specifically, the liner is adapted to providean improved interface in a prosthetic or orthopedic system between alimb and another prosthetic or orthopedic device via management ofperspiration occurring along the limb, prevention of slippage of thelimb and cushioning of the limb.

BACKGROUND

Numerous liners or padding are employed in prosthetic and orthopedicsystems, and serve as an interface between a corresponding prosthetic ororthopedic device and a limb.

By way of example, in the field of prosthetic devices, a liner sleeve isgenerally understood as a sleeve worn over a post-operative stump orlimb that serves as the interface between the limb and a prosthesis or aprosthetic device, such as a hard socket. Liners are typically made ofan air impermeable elastomer material, such as silicone. Liners maycomprise a single layer or multiple layers, with different layersproviding different benefits to the wearer.

Liners are used traditionally to cushion a post-operative stump or limbwith respect to a prosthesis that is installed over the limb and coupledto the sleeve by a conventional locking mechanism. The thickness of theliner may be increased to provide additional cushioning between the limband the prosthesis, thereby increasing comfort to the user.

In addition to providing cushioning, the liner also serves to protectthe limb from irritation that might be caused by movement of theprosthesis against the limb. In the absence of a liner, the prosthesiswill directly contact the skin. Any movement or slippage of theprosthesis at the interface with the limb will therefore result infriction between the prosthesis and limb and, consequently, irritationto the limb. Presence of the liner between the limb and the prosthesiseliminates this problem by serving as a protective barrier between thelimb and the prosthesis. In other words, movement at the interface withthe limb will be borne by the liner and not the limb.

Of course, in order for the liner to protect the limb from irritationcaused by movement of the prosthesis at the interface between theprosthesis and the limb, the liner preferably does not slip on the limb.That is to say, if the liner is capable of slipping on the limb, thenthe limb may become irritated by the friction caused by the linerrubbing against the skin of the limb.

Traditionally, liners have addressed this issue by utilizing a linerhaving a tacky surface for the surface that comes into direct contactwith the skin of the limb. The tacky inner surface of the liner ensuresthe liner does not slip or rub against the skin of the limb. The linerstays firmly in place against the limb, even when external forces suchas movement of the prosthesis against the external surface of the linerare acting on the liner.

The tacky inner surface of a liner does not always prevent slippage ofthe liner against the limb. Specifically, when the liner is made from anon-absorbent elastomer material, perspiration build-up in the linertends to cause the liner to lose suspension. The equal pressure appliedto the limb by the liner results in a thin film of perspiration formingand distributing throughout the liner. The thin film of perspirationforms an essentially frictionless gap between the limb and the liner,thus allowing the liner to easily slide on the limb. With no means toescape, the thin film of perspiration builds up between the limb andslippage of the liner is more likely to occur.

Liners find a variety of applications also in orthopedic devices forproviding an interface to the limb. Such liners may be used alone inreinforcing a limb, or may include reinforcing elements or be used incombination with braces for a variety of anatomical portions.

It is therefore one of the objects of the embodiments described hereinto create an improved liner that effectively manages perspiration formedby a limb, prevents slippage of the liner on the limb, and furtherprovide suitable cushioning for the limb. Such a liner can be used in avariety of applications for both prosthetic and orthopedic systems incombination with prosthetic and orthopedic devices.

SUMMARY

The present invention is directed, at least in part, to embodiments of aliner for prosthetic and orthopedic systems designed to effectivelymanage perspiration formed by a limb, prevent slippage of the liner onlimb, and further provide suitable cushioning for a limb. In theexemplary embodiments described herein, they are discussed and shownwithin the context of a liner in a prosthetic system and in combinationwith a residual limb and a hard socket. However, the liner of theinvention is not limited to such a prosthetic environment, and insteadembraces any application requiring perspiration management, preventionof slippage, or cushioning of the limb.

According to one embodiment, the liner comprises an elongate, generallyporous layer and a perforated inner layer located on the inner surfaceof the porous layer. The perforated inner layer conforms to the shape ofthe porous layer, thus forming a two-layer liner, with the limbcontacting the perforated inner layer.

The porous layer of the liner may be a three-dimensional woven syntheticmaterial. The three-dimensional material includes interconnected gapsand tunnels running throughout the material, thereby allowing for thetransport of liquid from one surface of the porous layer to the other.

In one variation of the embodiment, the liner further comprises an outerlayer located on the outer surface of the porous layer. Like theperforated inner layer located on the porous layer, the outer layerconforms to the shape of the porous layer. The outer layer is capable ofproviding additional beneficial characteristics, such as adding supportto the shape of the liner.

According to one configuration of the embodiment, at least one of theouter layer and the perforated inner layer is made from a polymermaterial. More specifically, the outer layer and inner layer are eachconstructed from silicone. Such materials can provide additionaldesirable characteristics to the liner, including structural support andcushioning.

The perforated inner layer may have a tacky inner surface for contactingthe skin of the limb. The tacky surface provides a safeguard against theliner slipping on the limb.

In one construction of the embodiment, the holes in the perforated innerlayer are larger than the pores of the porous layer. Such aconfiguration provides large spaces for perspiration formed by the limbto collect and then move into the smaller pores of the porous layer. Thelarge holes also decrease the area of the inner layer contacting theskin of the limb, and thereby reduce the opportunity for perspiration tocollect between the limb and the inner layer.

The thickness of the porous layer may also be greater than the thicknessof the perforated inner layer and the outer layer in order to dedicatemore of the total thickness of the liner to providing space and areasfor the perspiration to travel away from the limb.

In another variation of the embodiment, the outer layer is waterpermeable and the perforated inner layer is water impermeable. Such aconfiguration encourages perspiration formed at the limb to be drawntowards the holes in the perforated inner layer and into the porouslayer. This variation also provides a means of escape from the liner forthe perspiration once it has traveled through the porous layer andreached the outer layer.

Further, it is also possible to form the outer layer only in the distalarea of the liner. In this configuration, perspiration traveling throughthe porous layer will not be trapped at the outer surface of the porouslayer, while an attachment member for attaching a prosthesis may beattached on the outer layer at the distal area of the liner.

When an attachment member is located on the liner (whether the outerlayer is located only in the distal area of the liner or about theentire liner), the means for attachments may include, but are notlimited to, a seal-in suspension, a locking pin, a vacuum with sleeve,hook-and-loop fasteners, adhesions, or any other suitable means known tothe skilled person.

In another embodiment described herein, the liner comprises an elongatebase layer having a plurality of holes formed therein. The liner furtherincludes porous members filled in each of the holes in the base layerand a perforated inner layer located on the inner surfaces of the baselayer and porous members. The porous members provide a means forchanneling perspiration formed on the limb through and out of the liner,rather than collecting between the limb and the liner. Because theporous members extend through to the outer surface of the liner, theperspiration traveling through the porous members can exit the liner.Further, the perforated inner layer helps to channel the perspirationinto the porous members.

In another configuration of the embodiment, the porous members arethree-dimensional woven synthetic material. The three-dimensionalstructure provides interconnected gaps and tunnels through which theperspiration can travel. The gaps and tunnels of the three-dimensionalwoven synthetic material run through the entirety of the material,thereby providing a means for the perspiration to exit the liner.

The base layer and perforated inner layer may be made from a polymericbased material, such as silicone. The polymeric materials are able toprovide additional benefits to the liner, such as cushioning andsupport.

In one variation of the embodiment, the inner surface of the perforatedinner layer may be tacky. The tacky surface provides friction betweenthe liner and the limb, and further prevents slippage of the liner onthe limb. In addition, the perforations of the perforated inner layermay be larger than the pores of the porous layer such that theperspiration formed by the limb will be more likely to collect in theperforations of the inner liner and move into the porous members. Thisconfiguration also minimizes the surface area where perspiration maycollect between the inner layer and the limb. Using a water impermeablematerial for the perforated inner layer also tends to help channelperspiration towards the porous members.

In another configuration of the embodiment, the holes in the base layerare located between the distal and proximal areas of the base layer.When the distal area is free of holes with porous members formedtherein, the distal area is better suited for supporting a prosthesisattachment member. Such a prosthesis attachment member located in thedistal area of the liner may include a seal-in suspension, a locking pinand a vacuum with sleeve.

In another embodiment described herein, the liner comprises an elongateporous polymer foam layer and a porous silicone layer coated on both theinner and outer surfaces of the polymer foam layer. The porous polymerfoam is absorbent and therefore perspiration from the limb may passthrough the inner porous silicone coating and perspiration will absorbinto the porous foam layer rather than form thin films of perspirationbetween the liner and the limb.

In a variation of the embodiment, the liner also includes discreteportions of a moisture-absorbing material, such as in the form of apowder, to further aid in the absorption of perspiration. The portionsof the moisture-absorbing material may be embedded within the porouspolymer foam or may be located on the inner and outer surfaces of theporous polymer foam layer. In a further variation, the discrete portionsof moisture-absorbing material are located both within the polymer foamand on the inner and outer surfaces of the porous polymer foam layer.

It will be noted that discrete portions of a moisture-absorbing materialmay be provided in any of the types of porous layers described hereinsuch as by impregnating, embedding, meshing or injecting such discreteportions of moisture absorbing material in the porous layer.

In one construction, the porous polymer foam is porous silicone foam.The silicone foam may further include a plurality of hydrophilicparticles anchored to the pore walls of the foam.

The liner of the embodiment may include additional layers, such as anouter layer formed on the outer surface of the outer coating ofsilicone. Such layers are capable of providing additionalcharacteristics to the liner, such as support to keep the shape of theliner. The outer layer may be formed of porous or non-porous silicone.

In still a further embodiment described herein, the liner comprises apolymer construct wherein the construct is made from multiple layers ofpolymer threads. The layers of threads create gaps between whichperspiration from the limb may travel away from the limb and out of theliner.

In one variation of this embodiment, the polymer threads have agenerally rod-like shape. This configuration for the polymer threadshelps to ensure that adjacent threads do not block gaps or tunnels inwhich the perspiration is traveling.

The polymer threads within a single layer may be aligned in parallel.That is to say, the polymer threads of a layer have an organizedstructure whereby adjacent threads within the layer are parallel.Similarly, adjacent layers of polymer threads are aligned in parallelwhen stacked upon each other.

With respect to the orientation of polymer threads of different layers,the polymer threads of one layer are not aligned in parallel to polymerthreads in an adjacent layer. The polymer threads of a first layer maybe aligned at a 45 degree angle to polymer threads in an adjacent layer,or any other angle that creates gaps and tunnels in which perspirationmay travel away from the limb.

In yet another embodiment described herein, the liner comprises ayconical polymer construct, wherein the polymer construct is made ofmultiple layers of packed polymer balls. The layers of packed polymerballs create paths in which the perspiration formed on a limb may travelaway from the limb. By providing a path for the perspiration to travelaway from the limb, the build up of perspiration at the interface of thelimb and the liner will be prevented.

In one variation of the embodiment, the polymer balls are packed suchthat the balls are in contact with adjacent balls. The packed ballsconfigured in this manner will provide a compact liner layer while stillproviding gaps and tunnels in which the perspiration can travel due tothe ball shape. In still another variation of the embodiment, thepolymer balls are sphere balls. The polymer balls may also all have thesame diameter.

The embodiments described herein may be formed as a close-ended,generally conical sleeve, or may include opposed open ends. Moreover,the liner described herein is not limited tubular type constructions,but is intended to embrace any geometrical configuration having thelayer configurations described herein as pertaining to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical sectional view of an embodiment of a liner.

FIG. 2 is a sectional view corresponding to detail A in FIG. 1.

FIG. 3 is a cross-sectional view taken along line I-I in FIG. 1.

FIG. 4 is a detailed perspective view of the inner surface of the linerdepicted in FIG. 1.

FIG. 5 a vertical sectional view of another embodiment of a liner.

FIG. 6 is a cross-sectional view taken along line II-II in FIG. 5.

FIG. 7 is a cross-sectional view taken along line III-III in FIG. 5.

FIG. 8 is a sectional view corresponding to detail B in FIG. 5.

FIG. 9 is an elevational view of alternate forms of the liner depictedin FIG. 5.

FIG. 10 is a vertical sectional view of still another embodiment of aliner.

FIG. 11 is a vertical sectional view of an alternate form of theembodiment depicted in FIG. 10.

FIG. 12 is a vertical sectional view of an alternate form of theembodiment depicted in FIG. 10.

FIG. 13 is a vertical sectional view of an alternate form of theembodiment depicted in FIG. 10.

FIG. 14 is a vertical sectional view of yet another embodiment of aliner.

FIG. 15 is a detailed perspective view of the inner surface of the linerdepicted in FIG. 14.

FIG. 16 is a vertical sectional view of still another embodiment of aliner.

FIG. 17 is a detailed perspective view of the inner surface of the linerdepicted in FIG. 16.

In the various figures, similar elements are provided with similarreference numbers. It should be noted that the drawing figures are notnecessarily drawn to scale, but instead are drawn to provide a betterunderstanding of the components thereof, and are not intended to belimiting in scope, but rather provide exemplary illustrations.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

The embodiments described herein are each adapted to manage perspirationoriginating from a limb or other anatomical portion of a body whileproviding superior comfort. In the first and second exemplaryembodiments, the liner manages perspiration in part by using porousabsorbent layers or members to draw perspiration away from the limb. Inthe third exemplary embodiment, a porous polymer foam is used to drawperspiration away from the limb. In the fourth and fifth exemplaryembodiments, the liners are configured to provide paths and gaps betweena series of layers in which perspiration may travel away from the limb.

In the liner embodiments that follow, it will be noted that they aredescribed in the context of a liner sleeve for a limb. However, thiscontext is provided only for exemplary purposes since the lineraccording to the invention may be arranged in a variety of geometricalconfigurations for both prosthetic and orthopedic applications. In otherwords, the configuration of the liner is not limited in construction foruse as a liner sleeve in a particular system, and a liner in accordancewith the invention may not necessarily be geometrically configured as aclose-ended or even open-ended sleeve.

Such alternative configurations include sheets or segments for use incombination with braces, or configured for numerous other prosthetic andorthopedic applications. These sheets or segments may be tailored tocorrespond to elements of a prosthetic or orthopedic device, such as ina brace, and may be removably mounted for replacement or fixedly securedby known methods to the skilled person.

A. First Embodiment

In a first exemplary embodiment, the liner is formed as an elongate,closed-ended, generally conical shape porous layer wherein a perforatedinner layer is located on the inner surface of the porous layer and anouter layer is located on the outer surface of the porous layer.

As shown in FIG. 1, the liner 10 has an elongate, closed-ended,generally conical shape for receiving a limb having roughly the sameshape. The liner has a proximal end 12, which is open, and a distal end14, which is closed.

As shown in FIGS. 1, 2 and 3, the liner 10 includes a porous layer 16, aperforated inner layer 18 and an outer layer 20. The porous layer 16 hasan inside surface 18 and an outer surface 20 opposing the inner surface18. On the inner surface 18 of the porous layer 16, an inner layer 22having perforations 24 is defined. An outer layer 26 is defined on theouter surface 20 of the porous layer 16. The perforated inner layer 22and the outer layer 26 generally conform to the elongate, conical shapeof the porous layer 16, thus forming a tri-layered structure. The layersof the liner may be adhered together by any means known in the art, suchas through the use of an adhesive material or by lamination.

Perspiration formed in the areas of skin located over the perforationswill be channeled directly to the porous layer, where the perspirationwill begin to move through the tunnels and gaps of the porous layer andaway from the limb. Perspiration formed in the areas where skin contactsthe perforated inner layer will be directed towards the perforations andthe porous layer. This is especially the case at the edges of theperforated inner layer where holes are formed and are rounded. Therounded edges allow perspiration to roll down towards the porous layer.Using an impermeable material for the perforated inner layer will alsotend to promote the movement of perspiration from the perforated innerlayer towards the porous layer.

FIG. 1 depicts the outer layer 26 located co-extensively with the porouslayer 16. In other words, the outer layer 26 covers the entire outersurface 20 of the porous layer 16. In an alternate configuration, theouter layer is located in only the distal area 14 of the liner 10. Inthis manner, any perspiration that travels away from the limb via theporous layer will be able to exit the liner above the distal area sincethe outside surface of the porous layer is not contained by an outerlayer above the distal area. Additionally, the presence of the outerlayer in the distal area still allows the outer layer to provideadditional beneficial characteristics to the liner, such as supportingthe distal area of the liner and also providing a platform on which aprosthesis attachment member may be placed.

The liner may further include a prosthesis attachment member, whetherthe outer layer is located co-extensively with the porous layer or onlyin the distal area. Prosthesis attachment mechanisms known in the artmay be added to the liner, including, but not limited to, seal-insuspension elements, locking pins and vacuum elements.

The thickness of the liner may be varied depending on such factors suchas the amount of cushioning desired by the user. With respect to thethickness of each layer of the liner, the thickness of the layers islimited only by the total thickness of the liner desired.

In one variation of the embodiment, the thickness of the porous layermay be larger than the thickness of the perforated inner layer and theouter layer. The thickness of the porous layer may be greater than thethickness of the perforated inner layer and outer layer such that theporous layer is capable of managing a large amount of perspiration. Aporous layer with a greater thickness will have a greater capacity tostore perspiration. A larger storage capacity allows the user to wearthe liner for a longer period of time without needing to change or cleanthe liner. Such a configuration makes the liner especially useful whenthe desired function of the sleeve is to absorb and store perspirationrather than transport it out of the liner.

The overall size of the liner may be any size needed to fit the size ofthe limb of the user.

The porous layer may be made from any of a number of porous materialscapable of absorbing liquid and that are suitable for use in a liner.For example, the porous layer may be a three-dimensional woven syntheticmaterial, wherein the three-dimensional woven structure provides anetwork of pores, gaps and/or tunnels throughout the material in towhich perspiration may travel. The three-dimensional woven structure isalso such that these pores, gaps and/or tunnels are interconnected, andprovide a path from one surface of the porous layer to the opposingsurface. The three-dimensional woven structure may be synthetic in orderto increase the durability and longevity of the porous layer as comparedto natural materials. However, the porous layer suitable for theembodiment is not limited to synthetic materials where natural materialswill achieve common functionality.

A specific example of material suitable for use as the porous materialin the liner of the embodiment is made by TYTEX Group, Ikast, Denmarkunder product designation Quality No. 95289 and Tytex 5754/6.

The perforated inner layer may serve as the layer that comes into directcontact with the skin of the limb. It is therefore beneficial for theperforated inner layer to be tacky. In this manner, the perforated innerlayer helps to keep the liner in place on the limb and prevents slippagebetween the liner and limb.

The perforated inner layer may be any material suitable for use in aliner and which provides adequate distribution of perspiration formed bythe limb into the porous layer while remaining in place on the limb.Various polymers may be used for the perforated inner layer. Morespecifically, an example of a material that may be used for theperforated inner layer is silicone. As a hydrophobic material, siliconeis well suited for directing perspiration formed at the interface of thelimb and the perforated inner layer towards the porous layer. Any of thematerials suitable for use as the inner perforated layer, includingsilicone, may also be impermeable. An impermeable material will ensurethat water forming at or around the perforated inner layer will flow notinto the perforated inner layer, but rather will move towards and intothe perforations and subsequently in to the porous layer.

Perforations in the perforated inner layer extend from one surface ofthe perforated inner layer to the opposing surface of the inner surface.In this configuration, portions of the skin of the limb will contact theperforated inner layer, while other portions of the skin of the limb arelocated over the perforations, thereby forming a space between the skinof the limb and the porous layer.

The perforations of the inner layer may be larger than the pores of theporous layer, so as to provide larger areas for the perspiration tocollect before moving into the porous layer. Providing largerperforations also reduces the amount of perforated inner layercontacting the skin, thus making it more likely that perspirationforming on the limb will be over a perforation rather than between theperforated inner layer and the skin of the limb.

The outer layer may serve as the layer that comes into direct contactwith a prosthesis. The material of the outer layer, like the material ofthe perforated inner layer, may be any material suitable for use in aliner. The material of the outer layer may be a material that providesadditional beneficial characteristics to the sleeve, such as additionalsupport to the structure of the liner or additional cushioning toincrease the comfort of the user.

Various polymer materials may be used for the outer layer, such as, byexample, a silicone-based material. Any of the materials of the outerlayer may be permeable or impermeable. When permeable, the perspirationthat has traveled from the limb through the porous layer can then passthrough the outer layer to leave the liner. When impermeable, theperspiration travels from the limb through the porous layer and will beretained in the liner. In this configuration, the porous layer eitherretains the perspiration in order to keep liquid from collecting at theliner-limb interface or the liner will further comprise a means forexpelling perspiration that collects between the porous layer and theoutside layer, such as a drain.

Silicone material suitable for use in both the outer layer andperforated inner layer 22 is not limited, and may be the siliconeelastomer material described in U.S. Pat. Nos. 6,592,539 and 6,136,039,both of which are owned by the assignee of the pending application.

B. The Second Embodiment

In another exemplary embodiment, the liner is formed as an elongate,closed-ended, generally conical base layer with a plurality of holes,wherein the holes are filled with a porous material and a perforatedinner layer is located on the inner surface of the base layer.

As shown in FIGS. 5, 6, 7 and 8, the liner 40 has an elongate,closed-ended, generally conical shape for receiving a limb havingroughly the same shape. The liner has a proximal end 42, which is open,and a distal end 44, which is closed. The liner 40 includes a base layer46 with holes 52 located throughout the base layer 46, porous members 54filled in the holes 52, and a perforated inner layer 56. The base layer46 has an inside surface 48 and an outer surface 50 opposing the innersurface 48. The holes 52 extend from the inner surface 48 to the outersurface 50 of the base layer 46.

As is shown in FIGS. 5-9, the holes 52 are filled with porous members54. The porous members 54 inserted in the holes 52 fill the holes 52completely such that the surfaces of the porous members 54 at eitherside of the holes 52 are coplanar with the inner surface 48 and outersurface 50 of the base layer 46. The porous members 54 may be retainedin the holes 52 of the base layer 46 by any variety of means, includingan adhesive or by forming a tight fit between the porous member and thehole.

FIG. 9 depicts two exemplary configurations for the holes. In oneexemplary configuration, the holes 52 are vertically oriented ovalsarranged in columns, wherein the holes of a column are offset from theholes of an adjacent column. In this configuration, no holes are formedin the distal area of the liner. Each of these holes is filled with aporous member 54. In a second exemplary configuration, the holes 52 havean oval shape and are aligned in columns. The holes are oriented at anapproximately 45 degree angle, with each column being the mirroropposite of the adjacent column. In this configuration, no holes areformed at the distal end of the liner. A porous member 54 is located ineach of these holes 52.

It will be noted that that the size, shape, location and pattern of theholes are not limited to those shown in FIG. 9, and may be anyconfiguration suitable for use in a liner. The holes may be uniform insize and spaced in a consistent pattern, or the holes may vary in shapeand be placed randomly about the liner. However, the holes should not beso large or so numerous as to destroy the structural integrity of thebase layer.

The liner may further include a prosthesis attachment member, whether anouter layer is employed or not. The attachment mechanism may be formedin the distal area where no holes are formed. Any prosthesis attachmentmechanism known in the art may be added to the liner, including, but notlimited to, seal-in suspension, locking pin and vacuum with sleeve.

The thickness of the liner may be varied depending on such factors asthe amount of cushioning desired by the user. With respect to thethickness of each layer of the liner, the thickness of the layers islimited only by the total thickness of the liner desired. The base layermay be thicker than the perforated inner layer. As noted above, theporous member will typically have the same thickness as the base layerso that the surfaces of the porous members are coplanar with thesurfaces of the base layer.

The thickness of the base layer and porous members may be greater thanthe thickness of the perforated inner layer such that the porous membersare capable of managing a large amount of perspiration. A porous layerwith a greater thickness will have a greater capacity to storeperspiration. A larger storage capacity allows the user to wear theliner for a longer period of time without the necessity to change orclean the liner. Such a configuration makes the liner especially usefulwhen the desired function of the sleeve is to absorb and storeperspiration rather than transport it out of the liner.

The overall size of the liner may be any size needed to fit the size ofthe limb of the user.

The porous members in accordance with this embodiment may be made fromany of a number of porous materials capable of absorbing liquid and thatare suitable for use in a liner. For example, the porous members may bea three-dimensional woven synthetic material, wherein thethree-dimensional woven structure provides a network of pores, gapsand/or tunnels throughout the material in to which perspiration maytravel. The three-dimensional woven structure is also such that thesepores, gaps and/or tunnels are interconnected and provide a path fromone surface of the porous member to the opposing surface.

The three-dimensional woven structure may be synthetic in order toincrease the durability and longevity of the porous members as comparedto natural materials. However, the material suitable for the porousmembers of the embodiment is not limited to synthetic materials wherenatural materials will achieve common functionality.

A specific example of material suitable for use as the porous materialin the liner of the embodiment is made by TYTEX Group, Ikast, Denmarkunder product designation Quality No. 95289 and Tytex 5754/6.

The base layer may be any layer suitable for use in a liner. The baselayer may be a polymer material, and preferably is made of silicone. Thematerial may also be impermeable, which helps to guide the perspirationaway from the base layer and towards the holes filled with porousmembers.

The perforated inner layer may serve as the layer that comes into directcontact with the skin of the limb. It is therefore beneficial for theperforated inner layer to be tacky for the same reasons discussed abovein the first embodiment.

The perforated inner layer may be any material suitable for use in aliner and which provides adequate distribution of perspiration formed bythe limb into the porous members while remaining in place on the limb.Various polymers may be used for the perforated inner layer. Morespecifically, an example of a material that may be used for theperforated inner layer is silicone.

As discussed above in the first embodiment, silicone is a hydrophobicmaterial and is thus well suited for directing perspiration formed atthe interface of the limb and the perforated inner layer towards theporous members. Also as discussed above, certain advantages are achievedif the material of the inner perforated layer is impermeable.

Perforations in the perforated inner layer extend from one surface ofthe perforated inner layer to the opposing surface of the inner surface.In this configuration, portions of the skin of the limb will contact theperforated inner layer, while other portions of the skin of the limbwill be located over the perforations, forming a space between the skinof the limb and the porous members or base layer, depending on thelocation of the perforation.

The perforations of the perforated inner layer may be larger than thepores of the porous members, which will provide larger areas for theperspiration to collect before moving into the porous members. Providinglarger perforations also reduces the amount of the perforated innerlayer contacting the skin, thus making it more likely that perspirationforming on the limb will be over a perforation rather than between theperforated inner layer and the skin of the limb.

Perspiration formed in the areas of skin located over the perforationswill be funneled directly to the porous members or base layer. In theevent the perforation is located over the porous members, theperspiration will begin to move through the tunnels and gaps of theporous member and away from the limb. Additionally, perspiration formedin the areas where skin contacts the perforated inner layer will bedirected towards the perforations. As with the previous embodiment, aperforated inner layer made from impermeable material and having roundededges for the holes will also direct perspiration towards the porousmembers.

While not depicted in FIGS. 5-9, the liner of this embodiment may alsocomprise an outer layer located on the outer surface of the base layer.As described above with respect to the first embodiment, an outer layermay serve as the layer that comes into direct contact with a prosthesis.The layers of the liner may be adhered together by any means known inthe art, such as through the use of an adhesive material or bylamination.

The material of an outer layer, like the material of the perforatedinner layer, may be any material suitable for use in a liner. Thematerial of an outer layer may be a material that provides additionalbeneficial characteristics to the sleeve, such as additional support tothe structure of the liner or additional cushioning to increase thecomfort of the user.

Various polymer materials may be used for an outer layer, andspecifically, silicone may be used for an outer layer. As discussed inthe first embodiment, permeable or impermeable material may be used toachieve different effects.

As described in the first embodiment, the optional outer layer may belocated co-extensively with the base layer only the distal area of theliner.

Silicone material suitable for use in the base layer, the perforatedinner layer and the optional outer layer is not limited, and may be thesilicone elastomer material described in U.S. Pat. Nos. 6,592,539 and6,136,039, both of which are owned by the assignee of the pendingapplication.

C. The Third Embodiment

In still another exemplary embodiment, the liner is formed as anelongate, closed-ended, generally conical, porous foam layer having acoating of silicone on the outer and inner surfaces of the porous foamlayer. The liner of this embodiment may further comprise a discreteportion of a moisture-absorbing material, such as a powder, located in avariety of locations about the liner.

As shown in FIG. 10, the liner 60 has an elongate, closed-ended,generally conical shape for receiving a limb having roughly the sameshape. The liner has a proximal end, which is open, and a distal end,which is closed. The liner 60 includes a porous foam layer 62, an innersilicone coating 70 and an outer silicone coating 68 and an outer layer72.

The porous foam layer 62 comprises an outer surface 64 and an innersurface 66 opposing the outer surface 64. The porous foam layer 62further comprises a network of pores, gaps and/or tunnels that allowmoisture to pass into one surface of the porous foam layer, such as theinner layer 66, and pass through the porous foam layer to the oppositesurface, such as the outer surface 64. In this manner, the porous foamlayer 62 is capable of absorbing perspiration that forms inside of theliner and transporting it to the outside of the liner, thus preventingthe build up of liquid at the interface of the limb and the liner.

As also shown in FIG. 10, silicone layers 68, 70 may be formed on theinner surface 66 and outer surface 64 of porous foam layer 62. Innersilicone layer 70 is located on inner surface 66 of the porous foamlayer 62 while the outer silicone layer 68 is formed on the outersurface 64 of the porous foam layer 62. The inner and outer siliconelayers may be formed coextensively along the inner and outer surfaces ofthe porous foam layer. That is to say, the entire inner and outersurface of the porous foam layer is covered by the silicone layers.

As also shown in FIG. 10, the liner 60 may further comprise an outerlayer 72 formed on the outer silicone layer 68.

The porous foam layer may be made from any foam material suitable foruse in a liner and which has an ability to absorb and/or store moisture.The porous foam layer may be a porous polymer foam layer, andspecifically, may be a porous silicone foam layer. This embodiment alsocontemplates using the open-cell silicone foam with hydrophilicparticles as the porous foam layer disclosed in U.S. ProvisionalApplication No. 60/858,371, filed Nov. 13, 2006, and U.S. patentapplication Ser. No. 11/979,758, which are both incorporated herein byreference.

The inner silicone layer and outer silicone layer may both be permeableand/or porous, such that the silicone layers allow for liquid in theform of perspiration to pass through the layers. In this manner,perspiration may pass into the liner through the inner layer; travelthrough the porous foam layer and out of the liner via the outersilicone layer to effectively keep perspiration formed by the limb fromcollecting at the interface of the limb and the liner.

The silicone layers may also be thinner than the porous foam layer sothat perspiration travels easily through the layers into the porous foamlayer and allowing for the porous foam layer to account for the bulk ofthe thickness of the liner. The more of the liner that is dedicated tothe porous foam layer, the greater the capacity of the porous foam layerto store perspiration should the liner be designed to store excessperspiration.

The outer layer may be formed of any material suitable for use in theliner and the material for the outer layer will preferably be selectedfor its intended purpose. That is to say, if the outer layer is designedto add support to the liner, then the material should be more rigid. Thelayers of the liner may be adhered together by any means known in theart, such as through the use of an adhesive material or by lamination.

The outer layer may be a material such as a polymeric material, and morespecifically may be silicone. As described in previous embodiments, thematerial of the outer layer may also be either permeable of impermeable.

As shown in FIG. 11, a variation of a liner embodiment 61 includesdiscrete portions of a moisture-absorbing material 74 embedded withinthe porous foam layer 62.

The discrete portions of a moisture-absorbing material may be anymaterial suitable for absorbing and storing perspiration and which maybe embedded into foam. The discrete portions of the moisture-absorbingmaterial work in concert with the porous foam layer, either providingadditional means for absorbing and storing the perspiration or forabsorbing and storing excess perspiration that the liner is not capableof moving out to the liner.

The amount of moisture-absorbing material embedded into the porous foamlayer may also be varied depending on the demands of the user, with moremoisture-absorbing material present when the liner is aimed at absorbingand storing perspiration rather than transporting it out of the liner.

As shown in the liner variation 63 of FIG. 12, the moisture discreteportions of the moisture-absorbing material 74 may also be locatedbetween the silicone layers 68, 70 and the porous foam layer 62. In thismanner, the portions of moisture-absorbing material 74 help to draw themoisture through the inner silicone layer 70 into the porous foam layer62 at inner surface 66 and out of the porous foam layer 62 into theouter silicone layer 68 at the outer surface 64. As described above, anysuitable moisture-absorbing material and form thereof may be used andthe amount of the moisture-absorbing material 74 may vary based on thedemands of the user and how the liner is to function.

As shown in another liner variation 65 in FIG. 13, the discrete portionsof a moisture-absorbing material 74 are located both embedded within theporous foam layer 62 and between the silicone layers 68, 70 and withinthe porous foam layer 62 to draw on both of the attributes of thepreviously described variations of this embodiment.

The portions of moisture-absorbing material may be selected from anytype and form capable of absorbing moisture and suitable for use in aliner, and the amount of moisture-absorbing material at either locationmay be varied depending on the demands of the user and the desiredfunctionality of the liner.

As discussed above, each of the above variations of this embodiment mayalso be used when the porous foam layer is the material described inU.S. Provisional Application No. 60/858,371 and U.S. patent applicationSer. No. 11/979,758. In such a configuration, the portions ofmoisture-absorbing material work in concert with the hydrophilicparticles anchored to the pore walls of the porous material.

While the liner variations in FIGS. 11, 12 and 13, do not include anouter layer, each of the liners depicted are not prohibited from furtherincluding an outer layer should an outer layer be desired to provideadditional beneficial characteristics to the liners, such as additionalstructural support.

D. The Fourth Embodiment

In another exemplary embodiment, the liner is formed as an elongate,closed-ended, generally conical polymer construct comprising multiplelayers of polymer threads.

As shown in FIG. 14, the liner 80 has an elongate, closed-ended,generally conical shape for receiving a limb having roughly the sameshape. The liner 80 has a proximal end, which is open, and a distal end,which is closed. The liner 80 includes multiple layers 84 wherein eachlayer is made from a plurality of aligned polymer threads.

As shown in FIGS. 14, the liner has four layers 84, 86, 88, 90 ofpolymer threads. The layers 84 in the liner 80 may be at least two andthere may be any number of layers of threads available while stillexhibiting a thickness that is suitable for a liner. The inner surface82 of the liner 80 may be in direct contact with the skin of the limb.Because the inner surface 82 of the liner 80 is the inner most layer ofpolymer threads, the polymer threads of this layer will be in directcontact with the skin of the limb. Accordingly, the inner most polymerthread layer may be tacky to help reduce slippage between the liner andthe limb caused by perspiration forming at this interface.

As shown in FIG. 15, each of the layers 84, 86, 88, 90 of polymerthreads comprises a plurality of individual polymer threads 92 alignedin parallel. Also as shown in FIG. 15, each layer 84, 86, 88, 90 ofpolymer threads is aligned in the parallel to adjacent layers of polymerthreads. However, polymer threads in separate layers are not aligned inparallel.

The polymer threads 92 may be generally arranged in a circularcross-section. However, the shape of the polymer threads is not limitedto any specific geometric shape. The shape of the polymer threads mayhave cross sections in the shapes such as oval, pentagonal or hexagonal.The shape of the polymer threads should allow for gaps 94 to be createdbetween polymer threads 92 in a layer and between adjacent layers 84,86, 88, 90 of polymer threads. Such a configuration allows perspirationto travel through the layers of polymer threads via the gaps withoutbeing trapped within the plurality of layers.

The material of the polymer threads may be any suitable polymer for usein liners. As with previous embodiments, the polymer may be silicone.The silicone material is preferably impermeable, such that perspirationdoes not pass into the polymer threads but rather is directed towardsthe channels and gaps formed amongst the polymer threads and polymerthread layers.

The polymer threads of a layer may be oriented at an approximately 45degree angle from the polymer threads of the adjacent layer. The degreeat which each layer is offset is not limited and may be any degree ofoffset which maintains gaps between adjacent layers for perspiration totravel through.

The polymer threads and the layer of polymer threads may be adheredtogether by any means known in the art, such as through the use of anadhesive material or by lamination.

The size of the polymer threads is also not limited and may be any sizesuitable for use in a liner. Clearly, the cross section of the polymerthreads may not be so big as to make the polymer threads impractical foruse in a liner. Thus, the polymer threads should have a size such thatseveral layers of stacked polymer threads are not thicker than thethickness of a traditional liner.

The shape and size of the polymer threads need not be the same for allpolymer threads. That is to say, multiple shapes and sizes of polymerthreads may be used both within a layer of polymer threads and amongstdifferent layers of polymer threads. Again, so long as gaps and spacesare maintained in the liner for perspiration to travel through, theconfiguration is suitable for use in the liner disclosed herein. Thus,while FIG. 15 depicts polymer threads having the same circular shape andidentical diameters, alternate configurations may have different shapedand sized polymer threads.

When the liner as described above is worn in direct contact with theskin of a limb, perspiration forming on the limb will be directed intothe gaps and tunnels created between the polymer threads of each layer.The rounded edges of the polymer threads and use of an impermeablematerial for the polymer threads are two additional characteristics thatwill promote movement of perspiration into the gaps and tunnels.

The size of the gaps between polymer threads is not limited and may beany size that provides space between polymer threads for perspiration totravel. The objective is to allow space for perspiration to travel fromthe inner most layer of polymer threads to the outer most layer ofpolymer threads comprising the liner.

The gaps and tunnels amongst the polymer threads create a network thatextends to the outer most surface of polymer threads making up theliner. Once perspiration has traveled through the network to the outermost surface of polymer threads, the perspiration exits the liner.Accordingly, the liner provides a means for managing perspiration formedon the limb and moving the perspiration out of the liner. In thismanner, slippage between the liner and the limb due to accumulation ofperspiration at the interface is avoided.

E. The Fifth Embodiment

In another exemplary embodiment, the liner comprises a polymericconstruct comprising a plurality of packed polymeric balls.

As shown in FIG. 16, the liner 100 has an elongate, closed-ended,generally conical shape for receiving a limb having roughly the sameshape. The liner 100 has a proximal end, which is open, and a distalend, which is closed. The liner 100 includes multiple layers 104, 106,108, 110 wherein each layer is made from a plurality of packed polymericballs. The number of layers in the liner may be at least two and mayhave any number of layers of balls possible while still having athickness that is suitable for a liner.

The inner surface 102 of the liner 100 may be in direct contact with theskin of the limb. Because the inner surface 102 of the liner 100 is theinner most layer of polymeric balls, the polymer ball layer 110 will bein direct contact with the skin of the limb. Because of this, the innermost polymer ball layer may be tacky to help reduce slippage between theliner and the limb caused by perspiration forming at this interface.

As shown in FIG. 17, each polymeric balls layer comprises a plurality ofindividual polymeric balls 114. The polymeric balls 114 in a layer maybe configured such that all the balls touch adjacent balls. Thepolymeric ball layers may be stacked on top of each other such that eachpolymeric ball is directly on top of a polymeric ball in a lower layer,or, as shown in FIG. 17, the polymeric ball layers may be oriented suchthat the polymeric balls 114 of a layer are nestled into the spacebetween adjoining balls of the lower polymeric ball layer. In eitherevent, gaps 116 are maintained between the polymeric balls 114 andbetween the polymer ball layers such that a network of gaps and channelsexists to allow perspiration to travel from the inner most layer to theouter most layer.

The material of the polymeric balls may be any suitable polymer for usein liners. As with previous embodiment, the polymer may be silicone. Thesilicone material is preferably impermeable, such that perspiration doesnot pass into the polymeric balls but rather is directed towards thechannels and gaps formed amongst the polymeric balls and polymer balllayers.

The polymeric balls and the layer of polymeric balls may be adheredtogether by any means known in the art, such as through the use of anadhesive material or by lamination.

The shape of the polymeric balls is not limited to a perfect sphere. Inother words, oval balls may also be used as well as any otherthree-dimensional shape that does not close off gaps betweenthree-dimensional shapes and prevent perspiration from flowing throughthe network of gaps. While FIG. 17 shows the polymeric balls as having aspherical shape, the polymeric balls may also have other shapes, such asan oval shape. The shape of the polymeric balls should allow for gaps tobe created between polymeric balls in a layer and between adjacentlayers of polymeric balls. Such a configuration allows perspiration totravel through the layers of polymeric balls without being trappedwithin the plurality of layers.

The size of the gap between polymeric balls is not limited and may beany size that provides space between polymeric balls for perspiration totravel.

The size of the polymeric balls is also not limited and may be any sizesuitable for use in a liner. Clearly, the diameter of the polymericballs may not be so big as to make the polymeric balls impractical foruse in a liner. Thus, the polymeric balls should have a size such thatseveral layers of stacked polymeric balls are not thicker than thethickness of a traditional liner.

The shape and size of the polymeric balls need not be the same for allpolymeric balls. That is to say, multiple shapes and sizes of polymericballs may be used both within a layer of polymeric balls and amongstdifferent layers of polymeric balls. Again, so long as gaps and spacesare maintained in the liner for perspiration to travel through, theconfiguration is suitable for use in the liner disclosed herein. Thus,while FIG. 17 depicts polymeric balls having the same spherical shapeand identical diameters, alternate configurations may have differentshaped and sized polymeric balls.

When the liner as described above is worn in direct contact with theskin of a limb, perspiration forming on the limb will be directed intothe gaps and tunnels created between the polymeric balls of each layer.The rounded edges of the polymeric balls and use of an impermeablematerial are two additional characteristics that will promote movementof perspiration into the gaps and tunnels.

As seen in FIGS. 14 and 16, the liners do not include an outer layer.However, the liners depicted in FIGS. 14 and 16 are not prohibited fromfurther including an outer layer should the outer layer be desired toprovide additional beneficial characteristics to the liners such asstructural support. The characteristics and materials for such an outerlayer are similar to those described above with respect to earlierembodiments.

The disclosed embodiments of a liner provide improved management ofperspiration formed by a limb and consequently an improved liner that isless likely to slip on the limb and cause skin irritation to the limb.

It is understood that the size of the liners can be adjusted so thatdifferent users having different sized limbs may benefit from thepresent design.

Of course, it is to be understood that not necessarily all objects oradvantages may be achieved in accordance with any particular embodimentdescribed herein. Thus, for example, those skilled in the art willrecognize that the invention may be embodied or carried out in a mannerthat achieves or optimizes one advantage or group of advantages astaught herein without necessarily achieving other objects or advantagesas may be taught or suggested herein.

The skilled artisan will recognize the interchangeability of variousfeatures from different embodiments. In addition to the variationsdescribed herein, other known equivalents for each feature can be mixedand matched by one of ordinary skill in this art to construct a liner inaccordance with principles of the present invention.

Although this invention has been disclosed in the context of certainexemplary embodiments and examples, it therefore will be understood bythose skilled in the art that the present invention extends beyond thespecifically disclosed embodiments to other alternative embodimentsand/or uses of the invention and obvious modifications and equivalentsthereof. Thus, it is intended that the scope of the present inventionherein disclosed should not be limited by the particular disclosedembodiments described above.

1. A suspension liner having an elongate, closed-ended, generallyconical shape, the suspension liner comprising: a porous layer havinginner and outer surfaces, the porous layer defining pores; an innerlayer adjacent and adhered to the inner surface of the porous layer anddefining an inner surface of the suspension liner, the inner layerhaving perforations in communication with the pores of the porous layer,the perforations being larger than the pores of the porous layer, amaterial forming the inner layer being moisture impermeable; wherein theporous layer has a thickness greater than a thickness of the innerlayer.
 2. The suspension liner of claim 1, further comprising: an outerlayer adjacent and adhered to the outer surface of the porous layer. 3.The suspension liner of claim 2, wherein the inner and outer layers arecoextensive along the inner and outer surfaces of the porous layer. 4.The suspension liner of claim 3, wherein an entirety of the inner andouter surfaces of the porous layer is covered by the inner and outerlayers.
 5. The suspension liner of claim 2, wherein the outer layer isonly located along the porous layer in a distal area of the suspensionliner.
 6. The suspension liner of claim 5, wherein the porous layer isdefined relative to the outer layer so that perspiration travels throughthe outer surface thereof above the distal area of the suspension liner.7. The suspension liner of claim 2, wherein a thickness of the porouslayer is greater than a thickness of the outer layer.
 8. The suspensionliner of claim 2, wherein a material forming the outer layer is moistureimpermeable.
 9. The suspension liner of claim 2, wherein a materialforming the outer layer is moisture permeable.
 10. The suspension linerof claim 2, wherein the outer layer is more rigid than the inner layer.11. The suspension liner of claim 1, wherein the pores of the porouslayer define a network of pores permitting moisture to pass into atleast one of the inner and outer surfaces of the porous layer.
 12. Asuspension liner having an elongate, closed-ended, generally conicalshape, the suspension liner comprising: a porous layer having inner andouter surfaces, the porous layer defining pores; an inner layer adjacentand adhered to the inner surface of the porous layer and defining aninner surface of the suspension liner, the inner layer havingperforations in communication with the pores of the porous layer, theperforations being larger than the pores of the porous layer, a materialforming the inner layer being moisture impermeable; an outer layeradjacent and adhered to the outer surface of the porous layer; whereinthe porous layer has a thickness greater than a thickness of the innerlayer, and the thickness of the porous layer is greater than a thicknessof the outer layer; wherein the inner and outer layers are coextensivealong the inner and outer surfaces of the porous layer.
 13. Thesuspension liner of claim 12, wherein the outer layer is more rigid thanthe inner layer.
 14. The suspension liner of claim 12, wherein the poresof the porous layer define a network of pores permitting moisture topass into at least one of the inner and outer surfaces of the porouslayer.
 15. The suspension liner of claim 12, wherein the inner layer isformed from silicone.
 16. The suspension liner of claim 12, wherein theouter layer is formed from silicone.
 17. The suspension liner of claim12, wherein the porous layer is moisture absorbent.
 18. A suspensionliner having an elongate, closed-ended, generally conical shape, thesuspension liner comprising: a porous layer having inner and outersurfaces, the porous layer defining pores, the porous layer beingmoisture absorbent; an inner layer adjacent and adhered to the innersurface of the porous layer and defining an inner surface of thesuspension liner, the inner layer having perforations in communicationwith the pores of the porous layer, the perforations being larger thanthe pores of the porous layer, a silicone material forming the innerlayer being moisture impermeable; an outer layer adjacent and adhered tothe outer surface of the porous layer, the outer layer formed from asilicone material; wherein the porous layer has a thickness greater thana thickness of the inner layer, and the thickness of the porous layer isgreater than a thickness of the outer layer.
 19. The suspension liner ofclaim 18, wherein the porous layer defines the elongate, closed-ended,generally conical shape of the suspension liner and the inner and outerlayers conform to the elongate, closed-ended, generally conical shape ofthe porous layer, and the suspension liner defines a tri-layeredstructure.
 20. The suspension liner of claim 18, wherein the inner andouter layers are coextensive along the inner and outer surfaces of theporous layer.